NATO says a Russian invasion of Ukraine is "highly probable." The Ukrainian government says a large convoy of humanitarian aid coming from Russia is just a "Trojan horse." If the humanitarian crisis is indeed a pretext for an invasion, it certainly wouldn't be Moscow's first time.

The Budapest Festival Orchestra came to New York to play an all-Dvorak concert at Lincoln Center in New York. But the musicians were shocked when US Customs officials at JFK Airport seized seven bows belonging to the orchestra's string section. New federal regulations ban the commercial import of any and all elephant ivory - including the tips of classical violin bows.

Between them, Randy Kaplan and Zoltan Marian have collected more than 2000 autographs of heads of states, royals and popes. They share a kind of ethical code, but differ when it comes to who will they include in their collections.

If you serve as a volunteer, you know that it can feel good to devote your time to assisting others in need. But do you ever feel that you’re performing a job that deserves a paycheck? Volunteers around the world weigh in.

Our Geo Quiz takes us to the site of the Underworld Cup of Hungary. The event attracts hundreds of mountain bikers who enjoy the thrill of racing through a maze of dark, narrow tunnels in an abandoned limestone mine on the outskirts of Hungary's capital.